Field of the Invention
The present invention relates to a technology for recognizing a touch operation.
Description of the Related Art
Recently, technology that detects a plurality of points on a screen which has been touched, and executes an operation corresponding to the movement of those touched points has been developed. Such an operation that is performed based on touching of a plurality of points is known as a multi-touch operation.
In Japanese Patent Application Laid-Open No. 2011-227854, a scroll operation of a screen is performed by a drag operation in which two fingers in contact with the screen are moved in one direction without changing the distance between them. The scroll amount of the screen based on this operation is set to be twice that when a drag operation is performed with one finger. Specifically, the user can change the scroll amount by changing the number of touched points.
As in Japanese Patent Application Laid-Open No. 2011-227854, in an apparatus capable of performing a multi-touch operation, the operation content can change depending on whether one point was touched or two points were touched, for example.
However, the user may not always simultaneously bring the plurality of fingers into contact with the screen, or simultaneously release the fingers that were in contact with the screen. For example, even though the user may have intended to perform a two point touch, the user may actually touch one point first, and then touch the next point.
Further, recently touch panels have been used that detect and recognize the approach of a finger as a touch even without the finger actually coming into contact with the screen, a touched point on the apparatus may be detected even though the user intended to release his/her hand from the screen. Thus, immediately after the number of detected touched points has changed, there is both the possibility that the touched point is detected despite the fact that the user has already finished the operation, and the possibility that the user has intentionally changed the number of touching fingers in order to consecutively perform a plurality of operations.